利用百度语音API进行语音识别。

String fileName = "test.wav";
private MediaCapture _mediaCaptureManager;
private StorageFile _recordStorageFile;
private async void record_Click(object sender, RoutedEventArgs e)//点击后开始录音
{
　　try
　　{
　　　　//在临时文件夹Temp中创建文件，存在的话就替换掉
　　　　_recordStorageFile = await ApplicationData.Current.TemporaryFolder.CreateFileAsync(fileName, CreationCollisionOption.ReplaceExisting);
 　　　　//关键就是这俩句
　　　　MediaEncodingProfile recordProfile = MediaEncodingProfile.CreateWav(AudioEncodingQuality.Auto);//录音-WAV格式
   　　await _mediaCaptureManager.StartRecordToStorageFileAsync(recordProfile, this._recordStorageFile);//将录音保存到创建的文件中
　　}
　　catch (Exception ex)
　　{
　　　　Debug.WriteLine(ex.Message.ToString());
　　}
}
private async void stop_Click(object sender, RoutedEventArgs e)
{
　　await _mediaCaptureManager.StopRecordAsync();//停止录音
}

private void GetToken()
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create("https://openapi.baidu.com/oauth/2.0/token?grant_type=client_credentials&client_id="
                + "申请的API_KEY" + "&client_secret=" + “申请的SECRET_KEY”);
            request.BeginGetResponse(ResponseTokenCall, request);
        }

        private void ResponseTokenCall(IAsyncResult result)
        {
            try
            {
                HttpWebRequest httpWebRequest = (HttpWebRequest)result.AsyncState;
                WebResponse webResponse = httpWebRequest.EndGetResponse(result);
                using (Stream stream = webResponse.GetResponseStream())
                using (StreamReader reader = new StreamReader(stream))
                {
                    string content = reader.ReadToEnd();
                    string ssss = content.Replace("\"", "").Replace("{", "").Replace("}", "").Replace("\n", "");
                    string[] indexs = ssss.Split(‘,‘);
                    foreach (string index in indexs)
                    {
                        string[] _indexs = index.Split(‘:‘);
                        if (_indexs[0] == "access_token")
                            token = _indexs[1];//获取到的token
                    }
                }
            }

            catch (Exception ex)
            {
                Debug.WriteLine("获取Token失败");
            }
        }

private async void Post()
        {
            string serverURL = "http://vop.baidu.com/server_api?";
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(serverURL + "lan=zh&cuid=" + cuid + "&token=" + token);//cuid = Guid.NewGuid().ToString();  官方推荐使用 mac 地址/手机 IMEI 等类似参数，只要唯一就好 
            request.ContinueTimeout = 10000;//超时
            request.Method = "POST";//Post请求

            //post data
            request.BeginGetRequestStream(ResponseStreamCallbackPost, request);//Post数据
        }

        private async void ResponseStreamCallbackPost(IAsyncResult result)
        {
　　　       StorageFile storageFile = await ApplicationData.Current.TemporaryFolder.GetFileAsync(fileName);//取出临时文件夹中保存的音频文件

            IBuffer buffer = await FileIO.ReadBufferAsync(storageFile);//读取文件至Ibuffer
　　　       byte[] voice = WindowsRuntimeBufferExtensions.ToArray(buffer, 0, (int)buffer.Length);//将Ibuffer转换为byte[]
            
　　　　　    HttpWebRequest httpWebRequest = (HttpWebRequest)result.AsyncState;
            httpWebRequest.ContentType = "audio/wav;rate=8000";//参数设置
            using (Stream writeStream = httpWebRequest.EndGetRequestStream(result))
            {
                writeStream.Write(voice, 0, voice.Length);//写入
            }

            httpWebRequest.BeginGetResponse(ResponseCall, httpWebRequest);//发送请求
        }

        private void ResponseCall(IAsyncResult result)
        {
            try
            {
                HttpWebRequest httpWebRequest = (HttpWebRequest)result.AsyncState;
                WebResponse webResponse = httpWebRequest.EndGetResponse(result);
                using (Stream stream = webResponse.GetResponseStream())
                using (StreamReader reader = new StreamReader(stream))
                {
                    string content = reader.ReadToEnd();//返回的是utf-8编码
                    string a = Regex.Unescape(content);//进行转换
                }
            }
            catch (Exception ex)
            {
                Debug.WriteLine("识别失败");
            }
        }